//<p>给定一个二叉树，找出其最大深度。</p>
//
//<p>二叉树的深度为根节点到最远叶子节点的最长路径上的节点数。</p>
//
//<p><strong>说明:</strong>&nbsp;叶子节点是指没有子节点的节点。</p>
//
//<p><strong>示例：</strong><br>
//给定二叉树 <code>[3,9,20,null,null,15,7]</code>，</p>
//
//<pre>    3
//   / \
//  9  20
//    /  \
//   15   7</pre>
//
//<p>返回它的最大深度&nbsp;3 。</p>
//<div><div>Related Topics</div><div><li>树</li><li>深度优先搜索</li><li>广度优先搜索</li><li>二叉树</li></div></div><br><div><li>👍 1095</li><li>👎 0</li></div>

package leetcode.editor.cn;

public class _104_MaximumDepthOfBinaryTree {
    public static void main(String[] args) {
        Solution solution = new _104_MaximumDepthOfBinaryTree().new Solution();
    }
    //leetcode submit region begin(Prohibit modification and deletion)

    /**
     * Definition for a binary tree node.
     * public class TreeNode {
     * int val;
     * TreeNode left;
     * TreeNode right;
     * TreeNode() {}
     * TreeNode(int val) { this.val = val; }
     * TreeNode(int val, TreeNode left, TreeNode right) {
     * this.val = val;
     * this.left = left;
     * this.right = right;
     * }
     * }
     */
    class Solution {
        public int maxDepth(TreeNode root) {
            if (root==null) {
                return 0;
            }
            return Math.max(maxDepth(root.left),maxDepth(root.right))+1;
        }
    }
//leetcode submit region end(Prohibit modification and deletion)

}